基于知识规则的张臂式拉弯机三维拉弯过程控制
发布时间：2018-10-23 09:20
【摘要】：随着高铁领域的飞速发展,高铁车辆本身的生产需要也逐渐增加,用于制造高铁车头的蒙皮和车身的大梁均由张臂式拉弯机拉弯生产制成。在张臂式拉弯机的拉弯成形过程控制中,型材的拉伸力的大小、弯曲程度、回弹量和拉弯步进速度等是非常重要的工艺参量,直接影响着型材拉弯精度。然而,由于拉弯成形过程存在非线性、不确定性、机械误差和控制滞后等因素,单靠操作人员的经验难以实现有效控制,尤其是当工况变化时,很容易出现型材褶皱、拉断、弹飞伤人等问题,造成产品质量下降,消耗增加。针对以上情况,本文的主要内容与创新点概括为:1、基于张臂式拉弯机生产工艺理论,针对拉弯过程控制中型材的拉伸形变量进行研究。采用“加载轨迹”方法,通过控制拉弯机各个液压缸的运行轨迹来实现精准的拉弯过程控制。2、建立拉弯机物理模型,并应用到拉弯过程控制的数学模型中,通过模型计算出包覆角度,得到包覆角度与拉伸力的关系曲线,并初步确定各个液压缸的轨迹曲线。3、建立人机交互式加载轨迹模型,设计知识规则编辑器,在生产历史数据的支持下,基于实际加载轨迹,基于每个液压缸的预期运动轨迹,工艺专家调整并确认,通过知识编辑器生成知识规则,从而生成知识规则库。4、结合拉弯生产的实际情况,编写拉弯过程控制软件系统设计文档,并用C++编程实现该软件系统。针对张臂式拉弯机生产中的控制需求,将原来的手动单缸操作升级为空间三维四轴联动的自动过程控制,即回转臂缸、拉伸缸、升降缸和旋转缸联动。在实际型材拉弯成形生产的反馈中,拉弯过程完全实现自动控制,成形的型材表面光滑、拉弯精度符合工艺要求,验证了该拉弯过程控制系统的可行性、准确性,四轴联动的拉弯轨迹清晰直观,该拉弯过程控制系统已经投入于生产中。
[Abstract]:With the rapid development of high-speed rail industry, the production needs of high-speed railway vehicles have gradually increased. The skin used to make the front of high-speed railway cars and the beam of the body are all made by the stretch bending machine. In the process control of stretch bending process of tension bending machine, the drawing force, bending degree, springback and step speed of the profile are very important technological parameters, which directly affect the drawing and bending accuracy of the profile. However, due to the nonlinearity, uncertainty, mechanical error and control lag in the forming process of tension bending, it is difficult to realize effective control by the experience of the operator alone, especially when the working conditions change, the profile is prone to fold and break. Problems such as hurtful flying, resulting in a decline in product quality, consumption increased. In view of the above situation, the main contents and innovations of this paper are summarized as follows: 1. Based on the production technology theory of tension bending machine, this paper studies the drawing shape variables of the profile in the process control of tension and bending. By using the method of "loading track", the precise control of the bending process is realized by controlling the running track of each hydraulic cylinder of the bending machine. 2. The physical model of the bending machine is established and applied to the mathematical model of the control of the tension and bending process. The relationship curve between the coating angle and the tensile force is obtained by calculating the cladding angle, and the trajectory curve of each hydraulic cylinder is preliminarily determined. 3. The man-machine interactive loading trajectory model is established, and the knowledge rule editor is designed. Supported by the production history data, based on the actual loading trajectory, based on the expected motion trajectory of each hydraulic cylinder, the process expert adjusts and confirms, and generates the knowledge rules through the knowledge editor. Thus the knowledge rule base is generated. 4. According to the actual situation of tension bending production, the design document of the software system for the control of the process of tension bending is compiled, and the software system is realized by C programming. In view of the control requirement in the production of tension bending machine, the original manual single cylinder operation was upgraded to the automatic process control of three-dimensional four-axis linkage in space, that is, rotary arm cylinder, tension cylinder, lift cylinder and rotary cylinder. In the feedback of the actual profile forming process, the process of drawing and bending is completely controlled automatically, and the surface of the formed profile is smooth, and the precision of the bending is in line with the requirements of the process. The feasibility and accuracy of the control system for the process of drawing and bending are verified. The four-axis bending track is clear and intuitionistic, and the control system has been put into production.
【学位授予单位】：辽宁科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG355.3;TP273
[Abstract]:With the rapid development of high-speed rail industry, the production needs of high-speed railway vehicles have gradually increased. The skin used to make the front of high-speed railway cars and the beam of the body are all made by the stretch bending machine. In the process control of stretch bending process of tension bending machine, the drawing force, bending degree, springback and step speed of the profile are very important technological parameters, which directly affect the drawing and bending accuracy of the profile. However, due to the nonlinearity, uncertainty, mechanical error and control lag in the forming process of tension bending, it is difficult to realize effective control by the experience of the operator alone, especially when the working conditions change, the profile is prone to fold and break. Problems such as hurtful flying, resulting in a decline in product quality, consumption increased. In view of the above situation, the main contents and innovations of this paper are summarized as follows: 1. Based on the production technology theory of tension bending machine, this paper studies the drawing shape variables of the profile in the process control of tension and bending. By using the method of "loading track", the precise control of the bending process is realized by controlling the running track of each hydraulic cylinder of the bending machine. 2. The physical model of the bending machine is established and applied to the mathematical model of the control of the tension and bending process. The relationship curve between the coating angle and the tensile force is obtained by calculating the cladding angle, and the trajectory curve of each hydraulic cylinder is preliminarily determined. 3. The man-machine interactive loading trajectory model is established, and the knowledge rule editor is designed. Supported by the production history data, based on the actual loading trajectory, based on the expected motion trajectory of each hydraulic cylinder, the process expert adjusts and confirms, and generates the knowledge rules through the knowledge editor. Thus the knowledge rule base is generated. 4. According to the actual situation of tension bending production, the design document of the software system for the control of the process of tension bending is compiled, and the software system is realized by C programming. In view of the control requirement in the production of tension bending machine, the original manual single cylinder operation was upgraded to the automatic process control of three-dimensional four-axis linkage in space, that is, rotary arm cylinder, tension cylinder, lift cylinder and rotary cylinder. In the feedback of the actual profile forming process, the process of drawing and bending is completely controlled automatically, and the surface of the formed profile is smooth, and the precision of the bending is in line with the requirements of the process. The feasibility and accuracy of the control system for the process of drawing and bending are verified. The four-axis bending track is clear and intuitionistic, and the control system has been put into production.
【学位授予单位】：辽宁科技大学
【学位级别】：硕士
【学位授予年份】：2017
【分类号】：TG355.3;TP273
【参考文献】
相关期刊论文 前10条
1 赵军;殷t，
本文编号：2288795
本文链接：https://www.wllwen.com/kejilunwen/zidonghuakongzhilunwen/2288795.html
